This invention relates to an ink fountain for use in a printing press constructed to continuously supply a predetermined quantity of ink contained in an ink fountain.
An inking apparatus for supplying printing ink to a plate mounted on a plate of a rotary press generally includes an ink fountain device for supplying a predetermined quantity of ink stored in an ink fountain, and a plurality of roller groups for uniformly supplying to the plate the ink supplied from the ink fountain in various directions. The prior art ink fountain device is constructed as shown by a side view illustrated in FIG. 1. More particularly, there is provided an inclined blade support to the right and beneath an inking roller. Mounted on the upper surface of the blade support is an inking blade made of a resilient thin steel plate and having the same length as the axial length of the inking roller. The lower or outer end of the inking blade faces the periphery of the inking roller with a small gap therebetween. A plurality of adjusting screws arranged in the axial direction of the inking roller and equally spaced from each other by 20-50 mm are threaded through the bottom plate of the blade support to be reciprocable in a perpendicular direction with respect to the rear surface of the inking blade. In a triangular ink fountain defined by the periphery of the inking roller and the inking blade a quantity of printing ink is contained which flows out through a small gap between the periphery of the inking roller and the lower end of the inking blade. When the adjusting screws are advanced to press the rear surface of the inking blade, the gap is narrowed to decrease the quantity of the ink flowing out. Conversely, the quantity of ink flowing out can be decreased by retracting the adjusting screws. The quantity of the ink flowing out can be independently adjusted in respective sections along the inking roller by independently adjusting the adjusting screws, thereby adjusting the quantity of ink in accordance with the contrast of the pattern of the plate.
With such prior art ink fountain devices, however, since the inking blade is constituted by a single blade where it is desired to decrease the quantity of ink at portions corresponding to adjusting screws on both sides and to increase the quantity of ink at a portion corresponding to an intermediate adjusting screw as shown in FIG. 2, even when the adjusting screw is retracted while the adjusting screw are maintained in their advanced positions, the inking blade would not bend downwardly because it is depressed upwardly by the adjusting screws. To eliminate this difficulty, the adjusting screws on both sides are slightly retracted which results in a rough adjustment as shown in FIG. 3. Further, advancement of one adjusting screw has an influence on both sides thereof, thus failing to realize accurate adjustment.
Consequently, it has been proposed to divide the inking blade into a plurality of sections along the axis of the inking roller, which are adjustable independently. With this construction, however, the ink enters into the sliding surfaces of the blades and the blade support as well as the adjusting means through gaps between adjacent divided blade sections with the result that fine adjustment becomes impossible due to ink or its residue. It is a difficult operation to remove such ink or ink residue, thus making it difficult to maintain. According to another proposal, the divided blade sections are superimposed on inking blades in direct contact with the ink. In this construction, however, as the contact area between two blades is small, there is a tendency of the ink to leak to the outside.